Hello all,

I'm working a theatrical lighting system library for povray, based on LightSysIV
and CIE by Jaime and Ive, and I'm running into two problems with spotlights.

The first is trying to simulate a PARCan
<http://en.wikipedia.org/wiki/Parabolic_aluminized_reflector_light>, which is
an instrument with a lens that produces a soft-edged oval shape.
I've already implemented the standard spotlight with the built in function (with
beam and field angle), but can't figure this out without creating a complex
glass-textured asymmetrical solid lens. Does anyone know how to create this
effect?

The second is a problem with the color of the falloff of the standard spotlight.
If I use a light color that is slightly off-white (to be exact, using
Blackbody(3200) from CIE), the center of the beam is the correct color but it
changes from light yellow-ish to a deep orange between the beam radius and
falloff radius. This is projecting onto a pure white surface (diffuse 1 ambient
0), and using light fading. I didn't specify the fade_color, since I assume it
is black? How can I get rid of this effect, as it doesn't model real light
behavior at all? (possibly helpful addition: the original light color is way
over rgb 1.0 (closer to rgb 1*10000), to allow for a distant light)

Thanks for any help!

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